Could This Be the Fountain of Youth for Mice and Men?
Question 1 / 4
inject (v.)
inject (v.)
"In another experiment, they injected the protein into old mice."
Pick a word that you could use here for inject.
![](https://gdb.voanews.com/b043ff41-ac1b-42bb-8804-dd415717cc11_w250_r1_s.jpg)